Missing integration configuration tests

[ljacomet]

read-through and CacheLoader factory

In section 7.2 of the spec, it says (page 64):

Read-Through caching is set at configuration time by calling setReadThrough(boolean
isReadThrough) on MutableConfiguration. A CacheLoader Factory must also have been
defined.

There is currently no TCK test enforcing the must in that last sentence.

write-through and CacheWriter factory

In section 7.3 of the spec, it says (page 66):

Write-Through caching is set at configuration time by calling setWriteThrough(boolean
isWriteThrough) on MutableConfiguration. A CacheWriter Factory must also have
been defined.

Again, there is currently no TCK test enforcing the must in the last sentence.

Note that per javadoc of CacheManager.createCache(String, Configuration), the expected exception is an IllegalArgumentException.

[cruftex]

The Spec doesn't say something about the exact semantics of a missing configuration. Adding a TCK test would require a more precise Spec first.

See my comment on this here:
#69 (comment)

[cruftex]

Just a general note. The Spec says:

A CacheWriter Factory must also have been defined.

That kind of wording is has various ways to be interpreted. Usually, the Spec defines what a cache implementation "must do". Here it defines what a cache client "must do" and leaves the semantics of the cache implementation undefined.

If implementations should have the option to react different on error conditions / miss configuration a better wording would be:

An ambiguous situation exists when the write through is set to true but no cache writer is defined. The outcome is implementation specific.

[cruftex]

This this, since a duplicate.